Duplicate Cleaner is a powerful but potentially dangerous hard drive management tool for identifying duplicate files on your hard drives.
Tell the program which drives it should check, and the type of files it should examine - *.zip, say - and it'll go to work, crawling through every hard drive folder in the search for duplicate files. Once the process is complete, a detailed report will lists all your duplicates and allow you to select any you don't really need.
A separate tab lists files that are zero bytes in size. While these aren't exactly disk hogs, they are also consuming space in your file system, and removing them will give your PC a tiny speed boost (though not one you're likely to notice).
You do need to be extremely careful with Duplicate Cleaner, though. Every Windows PC requires some duplicate files within the \Windows folder, and erasing these will trash your installation: your system won't boot again. It's also conceivable that a zero-byte file could be performing some useful function for an application, in which case deleting it may cause odd behaviour. And so you must treat Duplicate Cleaner's reports with extreme caution, only removing files when you're entirely sure that they are unnecessary.
Duplicate Cleaner Free 3.1 is a minor upgrade with these changes:
-New 3.0 manual added, with contextual help buttons.
-All file removal/change operations are now logged in the log file (when enabled)
-Option to limit number of Duplicate files found in a scan
-Thumbnails can be turned off in image viewer
-New keyboard Shortcuts added.
-Select by Location: Copy selected path button added
-Bugfix: Incorrect filetimes returned in list with some files.
-Bugfix: Image viewer refresh + speed
-Bugfix: Localization fix
-Bugfix: File deletion memory/performance adjustments
-Bugfix: Other minor fixes.